drivers/soc/mediatek/mtk-devapc.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Copyright (C) 2020 MediaTek Inc.
   4  */
   5
   6 #include <linux/clk.h>
   7 #include <linux/interrupt.h>
   8 #include <linux/iopoll.h>
   9 #include <linux/module.h>
  10 #include <linux/platform_device.h>
  11 #include <linux/of.h>
  12 #include <linux/of_irq.h>
  13 #include <linux/of_address.h>
  14
  15 #define VIO_MOD_TO_REG_IND(m)   ((m) / 32)
  16 #define VIO_MOD_TO_REG_OFF(m)   ((m) % 32)
  17
  18 struct mtk_devapc_vio_dbgs {
  19         union {
  20                 u32 vio_dbg0;
  21                 struct {
  22                         u32 mstid:16;
  23                         u32 dmnid:6;
  24                         u32 vio_w:1;
  25                         u32 vio_r:1;
  26                         u32 addr_h:4;
  27                         u32 resv:4;
  28                 } dbg0_bits;
  29         };
  30
  31         u32 vio_dbg1;
  32 };
  33
  34 struct mtk_devapc_regs_ofs {
  35         /* reg offset */
  36         u32 vio_mask_offset;
  37         u32 vio_sta_offset;
  38         u32 vio_dbg0_offset;
  39         u32 vio_dbg1_offset;
  40         u32 apc_con_offset;
  41         u32 vio_shift_sta_offset;
  42         u32 vio_shift_sel_offset;
  43         u32 vio_shift_con_offset;
  44 };
  45
  46 struct mtk_devapc_data {
  47         /* numbers of violation index */
  48         u32 vio_idx_num;
  49         const struct mtk_devapc_regs_ofs *regs_ofs;
  50 };
  51
  52 struct mtk_devapc_context {
  53         struct device *dev;
  54         void __iomem *infra_base;
  55         struct clk *infra_clk;
  56         const struct mtk_devapc_data *data;
  57 };
  58
  59 static void clear_vio_status(struct mtk_devapc_context *ctx)
  60 {
  61         void __iomem *reg;
  62         int i;
  63
  64         reg = ctx->infra_base + ctx->data->regs_ofs->vio_sta_offset;
  65
  66         for (i = 0; i < VIO_MOD_TO_REG_IND(ctx->data->vio_idx_num) - 1; i++)
  67                 writel(GENMASK(31, 0), reg + 4 * i);
  68
  69         writel(GENMASK(VIO_MOD_TO_REG_OFF(ctx->data->vio_idx_num) - 1, 0),
  70                reg + 4 * i);
  71 }
  72
  73 static void mask_module_irq(struct mtk_devapc_context *ctx, bool mask)
  74 {
  75         void __iomem *reg;
  76         u32 val;
  77         int i;
  78
  79         reg = ctx->infra_base + ctx->data->regs_ofs->vio_mask_offset;
  80
  81         if (mask)
  82                 val = GENMASK(31, 0);
  83         else
  84                 val = 0;
  85
  86         for (i = 0; i < VIO_MOD_TO_REG_IND(ctx->data->vio_idx_num) - 1; i++)
  87                 writel(val, reg + 4 * i);
  88
  89         val = readl(reg + 4 * i);
  90         if (mask)
  91                 val |= GENMASK(VIO_MOD_TO_REG_OFF(ctx->data->vio_idx_num) - 1,
  92                                0);
  93         else
  94                 val &= ~GENMASK(VIO_MOD_TO_REG_OFF(ctx->data->vio_idx_num) - 1,
  95                                 0);
  96
  97         writel(val, reg + 4 * i);
  98 }
  99
 100 #define PHY_DEVAPC_TIMEOUT      0x10000
 101
 102 /*
 103  * devapc_sync_vio_dbg - do "shift" mechansim" to get full violation information.
 104  *                       shift mechanism is depends on devapc hardware design.
 105  *                       Mediatek devapc set multiple slaves as a group.
 106  *                       When violation is triggered, violation info is kept
 107  *                       inside devapc hardware.
 108  *                       Driver should do shift mechansim to sync full violation
 109  *                       info to VIO_DBGs registers.
 110  *
 111  */
 112 static int devapc_sync_vio_dbg(struct mtk_devapc_context *ctx)
 113 {
 114         void __iomem *pd_vio_shift_sta_reg;
 115         void __iomem *pd_vio_shift_sel_reg;
 116         void __iomem *pd_vio_shift_con_reg;
 117         int min_shift_group;
 118         int ret;
 119         u32 val;
 120
 121         pd_vio_shift_sta_reg = ctx->infra_base +
 122                                ctx->data->regs_ofs->vio_shift_sta_offset;
 123         pd_vio_shift_sel_reg = ctx->infra_base +
 124                                ctx->data->regs_ofs->vio_shift_sel_offset;
 125         pd_vio_shift_con_reg = ctx->infra_base +
 126                                ctx->data->regs_ofs->vio_shift_con_offset;
 127
 128         /* Find the minimum shift group which has violation */
 129         val = readl(pd_vio_shift_sta_reg);
 130         if (!val)
 131                 return false;
 132
 133         min_shift_group = __ffs(val);
 134
 135         /* Assign the group to sync */
 136         writel(0x1 << min_shift_group, pd_vio_shift_sel_reg);
 137
 138         /* Start syncing */
 139         writel(0x1, pd_vio_shift_con_reg);
 140
 141         ret = readl_poll_timeout(pd_vio_shift_con_reg, val, val == 0x3, 0,
 142                                  PHY_DEVAPC_TIMEOUT);
 143         if (ret) {
 144                 dev_err(ctx->dev, "%s: Shift violation info failed\n", __func__);
 145                 return false;
 146         }
 147
 148         /* Stop syncing */
 149         writel(0x0, pd_vio_shift_con_reg);
 150
 151         /* Write clear */
 152         writel(0x1 << min_shift_group, pd_vio_shift_sta_reg);
 153
 154         return true;
 155 }
 156
 157 /*
 158  * devapc_extract_vio_dbg - extract full violation information after doing
 159  *                          shift mechanism.
 160  */
 161 static void devapc_extract_vio_dbg(struct mtk_devapc_context *ctx)
 162 {
 163         struct mtk_devapc_vio_dbgs vio_dbgs;
 164         void __iomem *vio_dbg0_reg;
 165         void __iomem *vio_dbg1_reg;
 166
 167         vio_dbg0_reg = ctx->infra_base + ctx->data->regs_ofs->vio_dbg0_offset;
 168         vio_dbg1_reg = ctx->infra_base + ctx->data->regs_ofs->vio_dbg1_offset;
 169
 170         vio_dbgs.vio_dbg0 = readl(vio_dbg0_reg);
 171         vio_dbgs.vio_dbg1 = readl(vio_dbg1_reg);
 172
 173         /* Print violation information */
 174         if (vio_dbgs.dbg0_bits.vio_w)
 175                 dev_info(ctx->dev, "Write Violation\n");
 176         else if (vio_dbgs.dbg0_bits.vio_r)
 177                 dev_info(ctx->dev, "Read Violation\n");
 178
 179         dev_info(ctx->dev, "Bus ID:0x%x, Dom ID:0x%x, Vio Addr:0x%x\n",
 180                  vio_dbgs.dbg0_bits.mstid, vio_dbgs.dbg0_bits.dmnid,
 181                  vio_dbgs.vio_dbg1);
 182 }
 183
 184 /*
 185  * devapc_violation_irq - the devapc Interrupt Service Routine (ISR) will dump
 186  *                        violation information including which master violates
 187  *                        access slave.
 188  */
 189 static irqreturn_t devapc_violation_irq(int irq_number, void *data)
 190 {
 191         struct mtk_devapc_context *ctx = data;
 192
 193         while (devapc_sync_vio_dbg(ctx))
 194                 devapc_extract_vio_dbg(ctx);
 195
 196         clear_vio_status(ctx);
 197
 198         return IRQ_HANDLED;
 199 }
 200
 201 /*
 202  * start_devapc - unmask slave's irq to start receiving devapc violation.
 203  */
 204 static void start_devapc(struct mtk_devapc_context *ctx)
 205 {
 206         writel(BIT(31), ctx->infra_base + ctx->data->regs_ofs->apc_con_offset);
 207
 208         mask_module_irq(ctx, false);
 209 }
 210
 211 /*
 212  * stop_devapc - mask slave's irq to stop service.
 213  */
 214 static void stop_devapc(struct mtk_devapc_context *ctx)
 215 {
 216         mask_module_irq(ctx, true);
 217
 218         writel(BIT(2), ctx->infra_base + ctx->data->regs_ofs->apc_con_offset);
 219 }
 220
 221 static const struct mtk_devapc_regs_ofs devapc_regs_ofs_mt6779 = {
 222         .vio_mask_offset = 0x0,
 223         .vio_sta_offset = 0x400,
 224         .vio_dbg0_offset = 0x900,
 225         .vio_dbg1_offset = 0x904,
 226         .apc_con_offset = 0xF00,
 227         .vio_shift_sta_offset = 0xF10,
 228         .vio_shift_sel_offset = 0xF14,
 229         .vio_shift_con_offset = 0xF20,
 230 };
 231
 232 static const struct mtk_devapc_data devapc_mt6779 = {
 233         .vio_idx_num = 511,
 234         .regs_ofs = &devapc_regs_ofs_mt6779,
 235 };
 236
 237 static const struct mtk_devapc_data devapc_mt8186 = {
 238         .vio_idx_num = 519,
 239         .regs_ofs = &devapc_regs_ofs_mt6779,
 240 };
 241
 242 static const struct of_device_id mtk_devapc_dt_match[] = {
 243         {
 244                 .compatible = "mediatek,mt6779-devapc",
 245                 .data = &devapc_mt6779,
 246         }, {
 247                 .compatible = "mediatek,mt8186-devapc",
 248                 .data = &devapc_mt8186,
 249         }, {
 250         },
 251 };
 252 MODULE_DEVICE_TABLE(of, mtk_devapc_dt_match);
 253
 254 static int mtk_devapc_probe(struct platform_device *pdev)
 255 {
 256         struct device_node *node = pdev->dev.of_node;
 257         struct mtk_devapc_context *ctx;
 258         u32 devapc_irq;
 259         int ret;
 260
 261         if (IS_ERR(node))
 262                 return -ENODEV;
 263
 264         ctx = devm_kzalloc(&pdev->dev, sizeof(*ctx), GFP_KERNEL);
 265         if (!ctx)
 266                 return -ENOMEM;
 267
 268         ctx->data = of_device_get_match_data(&pdev->dev);
 269         ctx->dev = &pdev->dev;
 270
 271         ctx->infra_base = of_iomap(node, 0);
 272         if (!ctx->infra_base)
 273                 return -EINVAL;
 274
 275         devapc_irq = irq_of_parse_and_map(node, 0);
 276         if (!devapc_irq)
 277                 return -EINVAL;
 278
 279         ctx->infra_clk = devm_clk_get_enabled(&pdev->dev, "devapc-infra-clock");
 280         if (IS_ERR(ctx->infra_clk))
 281                 return -EINVAL;
 282
 283         ret = devm_request_irq(&pdev->dev, devapc_irq, devapc_violation_irq,
 284                                IRQF_TRIGGER_NONE, "devapc", ctx);
 285         if (ret)
 286                 return ret;
 287
 288         platform_set_drvdata(pdev, ctx);
 289
 290         start_devapc(ctx);
 291
 292         return 0;
 293 }
 294
 295 static void mtk_devapc_remove(struct platform_device *pdev)
 296 {
 297         struct mtk_devapc_context *ctx = platform_get_drvdata(pdev);
 298
 299         stop_devapc(ctx);
 300 }
 301
 302 static struct platform_driver mtk_devapc_driver = {
 303         .probe = mtk_devapc_probe,
 304         .remove = mtk_devapc_remove,
 305         .driver = {
 306                 .name = "mtk-devapc",
 307                 .of_match_table = mtk_devapc_dt_match,
 308         },
 309 };
 310
 311 module_platform_driver(mtk_devapc_driver);
 312
 313 MODULE_DESCRIPTION("Mediatek Device APC Driver");
 314 MODULE_AUTHOR("Neal Liu <neal.liu@mediatek.com>");
 315 MODULE_LICENSE("GPL");